Ian Evans has been handed a six-week suspension after being found guilty of foul play in Wales' 45-27 loss against Argentina in Buenos Aires on Saturday.
Wales and Ospreys lock Ian Evans' six-week ban will begin in August
The Ospreys lock was cited for wreckless and dangerous play for a late charge on Pumas captain Agustin Pichot.
The ban will run from the Ospreys' first friendly match in August.
"I regret the incident," Evans said. "I let the team down and discipline is something I will have to concentrate on in the future."
Evans, 21, is regarded as a possible future great by both Wales and the Ospreys, but has suffered from ill-discipline in his short professional career so far.
Ian will need to look at this aspect of his game
Wales team manager Alan Phillips
The lock was handed an eight-week ban last December for stamping on Leicester scrum-half Harry Ellis in a Heineken Cup match.
But Evans showed his potential on his Wales debut in last week's 27-25 first Test loss to the Pumas in Puerto Madryn.
The young lock intercepted a pass in midfield and raced 45 metres to score under the posts.
Wales team manager Alan Phillips said: "We were treated fairly in the hearing and we accept the punishment handed out to Ian.
"We have all learned lessons on this tour and this is one that Ian will have to take on board.
"He will need to look at this aspect of his game when he returns (to Wales)."